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In this article, the influence of trapezoidal magnetization method on cogging torque of permanent magnet motor is studied. First, the structure is analyzed by analytical method to explain its mechanism of reducing cogging torque. Then, in order to verify the effectiveness of the formula, a six-slot four-pole motor is introduced for finite element analysis. Through comparison of the original structure motor, the magnet skew structure motor, and the trapezoidal magnetic pole structure motor, it demonstrates that the trapezoidal magnetic pole structure motor can effectively reduce the Cogging torque and does not produce additional axial electromagnetic force. Finally, a magnetizing fixture with a trapezoidal magnetic pole structure is made to magnetize the magnetic ring. The magnetized magnetic ring is installed on the motor, and the Cogging torque, Back EMF, etc., are tested. The test results are in good agreement with the simulation results. This method can be used to optimize the cogging torque of the permanent magnet motor.

Antiferroelectric and ferroelectric materials are prominent non-linear dielectric materials with significant applications across various fields. To fully understand their electrical properties, it is crucial to accurately discriminate the two phases, especially in compositions with the coexistence of antiferroelectric and ferroelectric phases. In this study, we propose an easy method for differentiating domain structures from phase coexistence based on split outskirt reflections. The proposed method addresses existing limitations in the spatial phase distribution and lays the groundwork for understanding their structure–property relationships. [ABSTRACT FROM AUTHOR]

The electrochemical performance of all‐solid‐state lithium batteries (ASSLBs) can be significantly improved by addressing the challenges posed by space charge layer (SCL) effect, which plays a crucial role in determining Li+ ions transport kinetic at cathodic interface. Therefore, it is critical to realize the in situ inspection and visualization of SCL behaviors for solving sluggish Li+ ions transport issues, despite remaining grant challenges. Therewith, the well‐defined model of LiNbO3‐coated NCM (NCM@LNO) cathode is constructed and assembled for the representative Li6PS5Cl‐based ASSLBs, which not only ensures excellent cathodic compatibility, but also preferably enables the better monitoring of Li+ ions transport kinetics. Combining ex situ analysis with DFT calculation, the formation and evolution mechanism of SCL are comprehensively understood, and the relationship between well‐controlled SCL configuration and Li+ electrochemical behavior has been also further illustrated and established through the operando Raman spectroscopy. On these grounds, the preferred NCM@LNO cathodes acquire the enhanced discharge capacity of 90.6% (144.8 mAh g−1) after 100 cycles and it can still deliver the exceptional capacity of 136.2 mAh g−1 after 800 cycles in ASSLBs. Hence, the research will pave up a new perspective for fundamental scientific insight of the SCL and reasonable tailoring of cathodic interface for high‐efficiency ASSLBs. [ABSTRACT FROM AUTHOR]

SUMMARY: Gibberellins (GAs) play crucial roles in regulating plant architecture and grain yield of crops. In rice, the inactivation of endogenous bioactive GAs and their precursors by GA 2‐oxidases (GA2oxs) regulates stem elongation and reproductive development. However, the regulatory mechanisms of GA2ox gene expression, especially in rice reproductive organs, are unknown. The BEL1‐like homeodomain protein OsBLH4, a negative regulatory factor for the rice OsGA2ox1 gene, was identified in this study. Loss of OsBLH4 function results in decreased bioactive GA levels and pleiotropic phenotypes, including reduced plant height, decreased grain number per panicle, and delayed heading date, as also observed in OsGA2ox1‐overexpressing plants. Consistent with the mutant phenotype, OsBLH4 was predominantly expressed in shoots and young spikelets; its encoded protein was exclusively localized in the nucleus. Molecular analysis demonstrated that OsBLH4 directly bound to the promoter region of OsGA2ox1 to repress its expression. Genetic assays revealed that OsBLH4 acts upstream of OsGA2ox1 to control rice plant height, grain number, and heading date. Taken together, these results indicate a crucial role for OsBLH4 in regulating rice plant architecture and yield potential via regulation of bioactive GA levels, and provide a potential strategy for genetic improvements of rice. Significance Statement: GA 2‐oxidases (GA2oxs) play crucial roles in regulating plant architecture and yield by inactivating endogenous bioactive GAs and their precursors, but the regulatory mechanisms of GA2ox gene expression remain unclear. This study identifies that OsBLH4, a member of the BEL1‐like homeodomain proteins, acts upstream of OsGA2ox1, modulates endogenous bioactive GA levels, and regulates stem elongation and reproductive development in rice. [ABSTRACT FROM AUTHOR]

With the gradual promotion of new energy technologies, there is a growing demand for capacitors with high energy storage density, high operating temperature, high operating voltage, and good temperature stability. In recent years, researchers have been devoted to improving the energy storage properties of lead‐based, titanium‐based, and iron‐based multilayer ceramic capacitors (MLCCs). However, limited research has been conducted into MLCC development using NaNbO3 (NN)‐based materials. In this paper, the successful achievement of excellent overall energy storage performance in a novel NaNbO3–(Bi0.5Na0.5)TiO3–Bi(Mg0.5Hf0.5)O3 lead‐free MLCCs is presented. The disordered tilting around the cp axis, disrupts Na and Bi ions' long‐range displacements and induces PNRs and strong relaxor behavior, which ensures a superior energy storage performance, together with the multilayer ceramic design strategy. As a result, the NN‐based MLCC device presents an ultra‐high Wrec = 12.65 J cm−3 and η = 88.5%, simultaneously showing superior temperature stability (Wrec varies <±1% and η varies <±6% from −50 to 125 °C) and fatigue resistance (Wrec and η vary <±1% over 107 cycles). This study highlights the advanced energy storage potential of NaNbO3‐based MLCCs for various applications, and ushers in a new era for designing high‐performance lead‐free capacitors that can operate in harsh environments. [ABSTRACT FROM AUTHOR]

The capacitors are in rising demand for cryogenic applications. As for now, it still remains an ongoing challenge for simultaneously achieving high energy storage density and cryogenic temperature stability. Herein, the strategy of stable backward phase transition was demonstrated in the antiferroelectric composition of (Pb0.9175La0.055)(Zr0.975Ti0.025)O3. As a result, we achieved high recoverable energy density about 10 J/cm3 with exceptional low-temperature stability from −160 to 25 °C. Multi-layer ceramic capacitors designed for pulse discharge applications also demonstrated high performance in cryogenic conditions, with the peak current fluctuations of less than 4%. Through in situ characterizations using x-ray diffraction, Raman spectra, and transmission electron microscopy, we discovered that the anisotropic structural evolution is responsible for a stable backward phase transition, providing the material with robust stability at cryogenic temperatures. These results offer a good paradigm for improving the temperature stability of antiferroelectric multi-layer capacitors to meet the rigorous demands of energy storage applications. [ABSTRACT FROM AUTHOR]

Dielectric capacitors with a fast charging/discharging rate, high power density, and long‐term stability are essential components in modern electrical devices. However, miniaturizing and integrating capacitors face a persistent challenge in improving their energy density (Wrec) to satisfy the specifications of advanced electronic systems and applications. In this work, leveraging phase‐field simulations, we judiciously designed a novel lead‐free relaxor ferroelectric material for enhanced energy storage performance, featuring flexible distributed weakly polar endotaxial nanostructures (ENs) embedded within a strongly polar fluctuation matrix. The matrix contributes to substantially enhanced polarization under an external electric field, and the randomly dispersed ENs effectively optimize breakdown phase proportion and provide a strong restoring force, which are advantageous in bolstering breakdown strength and minimizing hysteresis. Remarkably, this relaxor ferroelectric system incorporating ENs achieves an exceptionally high Wrec value of 10.3 J/cm3, accompanied by a large energy storage efficiency (η) of 85.4%. This work introduces a promising avenue for designing new relaxor materials capable of capacitive energy storage with exceptional performance characteristics. [ABSTRACT FROM AUTHOR]

Antiferroelectric ceramics can realize ultra-high energy storage, which benefits from transformation between an antiferroelectric phase and a ferroelectric phase. Understanding the mechanism of such phase transition is the key point for building the structure-property correlation. Here, we report the observation of electric-induced devil's staircase in the course of antiferroelectric–ferroelectric phase transition in PbZrO3-based antiferroelectric ceramics by in situ transmission electron microscopy. The dynamic evolution as-revealed in both reciprocal- and real-space involves stepwise rather than monotonic increase in modulation periods along with simultaneous proliferation of nanodomains. Desynchrony of phase transition is observed for incommensurate domains with different initial modulation periods within a single antiferroelectric domain. Then, the synergistic effect of the devil's staircase and as small as possible the initial modulation period is believed to contribute to the superior energy-storage performance. These findings will be helpful for the development of theories for antiferroelectric–ferroelectric phase transition and the design of high-power antiferroelectric materials. [ABSTRACT FROM AUTHOR]

Si3N4 ceramics have been attractive casing materials for electronics devices under the 5th generation mobile communication technology because of its outstanding comprehensive properties. However, single color cannot meet the needs of most consumers. Here, a typical strategy, involving forming core‐shell structures by utilizing Nd2O3‐MgO‐YAG system, is proposed to rich color. Scanning transmission electron microscope‐energy dispersive X‐ray spectrometry results confirm the presence of core‐shell structures in the silicon nitride matrix, and the core is pore and the shell is Nd‐enriched liquid phase. The Nd‐rich core‐shell structure as the color center makes the silicon nitride appear cyan or blue. [ABSTRACT FROM AUTHOR]

Flavor wheel is a simple and easy method to understand descriptor system, which is convenient for consumers to communicate the sensory flavor attributes of Pu'er tea and Fu brick tea. In this study, by establishing a sensory evaluation team, sensory evaluation was conducted on the flavor of Pu'er tea and Fu brick tea, and the flavor wheels of Pu'er tea and Fu brick tea were drawn from two dimensions: aroma and taste. On this basis, a vocabulary for quantitative sensory description of Pu'er tea and Fu brick tea was established by setting reference samples with different intensities for 23 typical sensory descriptions. Furthermore, using the M-value method combined with analysis of variance and multivariate statistical analysis, the main sensory descriptors that can better describe Pu'er tea and Fu brick tea were selected. A total of 7 aroma descriptors (woody, sweet aroma, herbal, ferment, glutinous, jujube and aged) and 5 flavor descriptors (sweet taste, bitter, astringent, sour and mellow and thick) were selected for Pu'er tea, and 5 aroma descriptors (woody, sweet aroma, herbal, aged and fungal floral) and 5 flavor descriptors (sweet taste, bitter, astringent, sour and mellow and thick) were identified for Fu brick tea, and these descriptors can better evaluate the sensory quality characteristics of Pu'er tea and Fu brick tea samples. The results of this study provide application value for distinguishing and evaluating the sensory flavor characteristics of Pu'er tea and Fu brick tea, as well as in the development of their products. [ABSTRACT FROM AUTHOR]